This forces the output timing to fulfill
dTS = dSegNo * fixedPacketDuration
where dSegNo = seqNo - lastSeqNo.
If timestamp patching is enabled, the output timestamp will be set
to lastTimestamp + dTS. This kind of relative updating is used to
handle seqNo- and timestamp-wraparounds properly.
Ticket: OW#1065
Sponsored-by: On-Waves ehf
---
openbsc/src/libmgcp/mgcp_network.c | 21 ++++++++++++++++
openbsc/tests/mgcp/mgcp_test.ok | 48 ++++++++++++++++++------------------
2 files changed, 45 insertions(+), 24 deletions(-)
diff --git a/openbsc/src/libmgcp/mgcp_network.c
b/openbsc/src/libmgcp/mgcp_network.c
index b9bfc5e..a68c43c 100644
--- a/openbsc/src/libmgcp/mgcp_network.c
+++ b/openbsc/src/libmgcp/mgcp_network.c
@@ -308,6 +308,27 @@ void mgcp_patch_and_count(struct mgcp_endpoint *endp,
struct mgcp_rtp_state *sta
state->in_stream.last_timestamp = timestamp;
state->in_stream.last_seq = seq;
+ if (rtp_end->force_constant_timing &&
+ state->out_stream.ssrc == ssrc && state->packet_duration) {
+ int delta_seq = seq + state->seq_offset -
state->out_stream.last_seq;
+ int timestamp_offset =
+ state->out_stream.last_timestamp - timestamp +
+ delta_seq * state->packet_duration;
+ if (state->timestamp_offset != timestamp_offset) {
+ state->timestamp_offset = timestamp_offset;
+ state->patch = 1;
+
+ LOGP(DMGCP, LOGL_NOTICE,
+ "Timestamp patching enabled on 0x%x SSRC: %u "
+ "SeqNo delta: %d, TS offset: %d, "
+ "from %s:%d in %d\n",
+ ENDPOINT_NUMBER(endp), state->in_stream.ssrc,
+ delta_seq, state->timestamp_offset,
+ inet_ntoa(addr->sin_addr), ntohs(addr->sin_port),
+ endp->conn_mode);
+ }
+ }
+
/* apply the offset and store it back to the packet */
if (state->patch) {
seq += state->seq_offset;
diff --git a/openbsc/tests/mgcp/mgcp_test.ok b/openbsc/tests/mgcp/mgcp_test.ok
index 71293ad..c018fb2 100644
--- a/openbsc/tests/mgcp/mgcp_test.ok
+++ b/openbsc/tests/mgcp/mgcp_test.ok
@@ -78,32 +78,32 @@ Testing packet error detection, patch timestamps.
TS: 0, dTS: 0, TS Errs: in 0, out 0
TS: 160, dTS: 160, TS Errs: in 0, out 0
TS: 320, dTS: 160, TS Errs: in 0, out 0
-TS: 320, dTS: 160, TS Errs: in 1, out 1
-TS: 480, dTS: 160, TS Errs: in 1, out 1
-TS: 640, dTS: 160, TS Errs: in 1, out 1
-TS: 960, dTS: 320, TS Errs: in 2, out 2
-TS: 1120, dTS: 160, TS Errs: in 3, out 3
-TS: 1280, dTS: 160, TS Errs: in 3, out 3
-TS: 1400, dTS: 120, TS Errs: in 4, out 4
-TS: 1560, dTS: 160, TS Errs: in 5, out 5
-TS: 1720, dTS: 160, TS Errs: in 5, out 5
-TS: 34688, dTS: 160, TS Errs: in 5, out 5
-TS: 34848, dTS: 160, TS Errs: in 5, out 5
-TS: 35008, dTS: 160, TS Errs: in 5, out 5
+TS: 480, dTS: 160, TS Errs: in 1, out 0
+TS: 640, dTS: 160, TS Errs: in 1, out 0
+TS: 800, dTS: 160, TS Errs: in 1, out 0
+TS: 960, dTS: 160, TS Errs: in 2, out 0
+TS: 1120, dTS: 160, TS Errs: in 3, out 0
+TS: 1280, dTS: 160, TS Errs: in 3, out 0
+TS: 1440, dTS: 160, TS Errs: in 4, out 0
+TS: 1600, dTS: 160, TS Errs: in 5, out 0
+TS: 1760, dTS: 160, TS Errs: in 5, out 0
+TS: 34728, dTS: 160, TS Errs: in 5, out 0
+TS: 34888, dTS: 160, TS Errs: in 5, out 0
+TS: 35048, dTS: 160, TS Errs: in 5, out 0
Testing packet error detection, patch SSRC, patch timestamps.
TS: 0, dTS: 0, TS Errs: in 0, out 0
TS: 160, dTS: 160, TS Errs: in 0, out 0
TS: 320, dTS: 160, TS Errs: in 0, out 0
-TS: 320, dTS: 160, TS Errs: in 1, out 1
-TS: 480, dTS: 160, TS Errs: in 1, out 1
-TS: 640, dTS: 160, TS Errs: in 1, out 1
-TS: 960, dTS: 320, TS Errs: in 2, out 2
-TS: 1120, dTS: 160, TS Errs: in 3, out 3
-TS: 1280, dTS: 160, TS Errs: in 3, out 3
-TS: 1400, dTS: 120, TS Errs: in 4, out 4
-TS: 1560, dTS: 160, TS Errs: in 5, out 5
-TS: 1720, dTS: 160, TS Errs: in 5, out 5
-TS: 1880, dTS: 160, TS Errs: in 5, out 5
-TS: 2040, dTS: 160, TS Errs: in 5, out 5
-TS: 2200, dTS: 160, TS Errs: in 5, out 5
+TS: 480, dTS: 160, TS Errs: in 1, out 0
+TS: 640, dTS: 160, TS Errs: in 1, out 0
+TS: 800, dTS: 160, TS Errs: in 1, out 0
+TS: 960, dTS: 160, TS Errs: in 2, out 0
+TS: 1120, dTS: 160, TS Errs: in 3, out 0
+TS: 1280, dTS: 160, TS Errs: in 3, out 0
+TS: 1440, dTS: 160, TS Errs: in 4, out 0
+TS: 1600, dTS: 160, TS Errs: in 5, out 0
+TS: 1760, dTS: 160, TS Errs: in 5, out 0
+TS: 1920, dTS: 160, TS Errs: in 5, out 0
+TS: 2080, dTS: 160, TS Errs: in 5, out 0
+TS: 2240, dTS: 160, TS Errs: in 5, out 0
Done
--
1.7.9.5
